Abstract: An irrigation system having an irrigation controller, a means for detecting changes in environmental conditions, a valve, and a sprinkler connected to a irrigation supply. The controller controls the operation of the valve and the sprinkler in accordance with an irrigation schedule to selectively irrigate a specified number of vegetation areas. The irrigation schedule is adjusted automatically in response to changing environmental conditions. The irrigation schedule is created based on a number of input parameters including the number of cycles to be executed each day, the duration of each cycle, and the number of days in the irrigation period. After receiving the appropriate input parameters, the controller then automatically determines the days within the irrigation period on which irrigation should occur.

Abstract: The invention bypasses a need for human participation in the process of remotely controlling irrigation sprinklers using Evapotranspiration (ET) values. In one embodiment, a transmitter broadcasts updated Evapotranspiration (ET) data directly to a collection of receiver/controller units using an FM subcarrier. These receiver/controller units are microprocessor-based and coupled to a set of irrigation sprinklers.The method provides for broadcasting an encoded ET data signal to a collection of receiving and irrigation-controlling units. The receiving and irrigation-controlling units include microprocessor means and storage means for storing a preset ET zone reference and crop adjustment values. The method also includes receiving and decrypting an encrypted ET data signal into a broadcast ET zone identifier and a broadcast corresponding ET value. The method further compares the broadcast ET zone identifier with the preset ET zone reference.

Abstract: The invention permits modification of the operation of irrigation controllers at a plurality of sites without investment in any additional equipment except for one paging receiver per site.